\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{patterns}
\begin{document}
\footnotesize
  \begin{tikzpicture}[>=stealth,scale=1.5]
    \draw[pattern={north east lines}](-1.45,1.05)rectangle(1.45,1.35);
    \draw[pattern={north east lines}](-0.15,-1.15)rectangle(0.15,0.90);
    \fill[white](-1.4,0.95)--++(0,0.15)--++(30:0.1)--++(150:0.2)--++(30:0.1)--++(0,0.15)--++(-0.1,0)--++(0,-0.5)--cycle;
    \fill[white](1.4,0.95)--++(0,0.15)--++(30:0.1)--++(150:0.2)--++(30:0.1)--++(0,0.15)--++(0.1,0)--++(0,-0.5)--cycle;
    \fill[white](-0.25,-1.1)--++(0.15,0)--++(60:0.1)--++(-60:0.2)--++(60:0.1)--++(0.15,0)--++(0,-0.1)--++(-0.5,0)--cycle;
    \draw[thin](-1.4,0.95)--++(0,0.15)--++(30:0.1)--++(150:0.2)--++(30:0.1)--++(0,0.15);
    \draw[thin](1.4,0.95)--++(0,0.15)--++(30:0.1)--++(150:0.2)--++(30:0.1)--++(0,0.15);
    \draw[thin](-0.25,-1.1)--++(0.15,0)--++(60:0.1)--++(-60:0.2)--++(60:0.1)--++(0.15,0);
    \draw[very thin,](-0.45,1)--++(0.9,0);
    \draw[very thin,](-0.19,0.60)--++(0,0.34)--++(0.38,0)--++(0,-0.34);
    \foreach \x in {0.45,0.15}
      {
        \draw[thin](\x,1.05)--++(0,0.55);
        \draw[thin](-\x,1.05)--++(0,0.55);
      }
    \draw[thin,<->](-0.15,1.5)--++(0.3,0)node[midway,above]{$t$};
    \foreach \x in {-0.45,0.15} 
      { 
        \draw[thin,<->](\x,1.5)--++(0.3,0)node[midway,above]{30};
      }
    \draw[thin](-0.2,0.90)--++(-0.3,0);
    \draw[thin](-0.2,0.60)--++(-0.3,0);
    \draw[thin,<->](-0.4,0.60)--++(0,0.3)node[midway,above,sloped]{30};
    
    \begin{scope}[xshift=2.5cm]
      \draw[pattern={north east lines}](0.25,1.05)rectangle(1.85,1.35);
    \draw[pattern={north east lines}](-0.15,-1.15)rectangle(0.15,1.35);

    \fill[white](1.8,0.95)--++(0,0.15)--++(30:0.1)--++(150:0.2)--++(30:0.1)--++(0,0.15)--++(0.1,0)--++(0,-0.5)--cycle;
    \fill[white](0.5,1.35)--++(-0.3,-0.3)--++(0,0.4)--++(0.3,0)--cycle;
    \fill[white](-0.25,-1.1)--++(0.15,0)--++(60:0.1)--++(-60:0.2)--++(60:0.1)--++(0.15,0)--++(0,-0.1)--++(-0.5,0)--cycle;
    \draw[thin](1.8,0.95)--++(0,0.15)--++(30:0.1)--++(150:0.2)--++(30:0.1)--++(0,0.15);
    \draw[thin](-0.25,-1.1)--++(0.15,0)--++(60:0.1)--++(-60:0.2)--++(60:0.1)--++(0.15,0);
    \draw[very thin](-0.15,1.39)--++(0.34,0)--++(0,-0.34);
    \draw[very thin](0.21,1.05)--(0.21,1.1166)--(0.4834,1.39)--(0.7,1.39);
    \draw[thin](-0.15,1.40)--++(0,0.2);
    \draw[thin](0.15,1.40)--++(0,0.2);
    \draw[thin](0.7,1.40)--++(0,0.2);
    \draw[thin](0.5,1.40)--++(0,0.2);
    \draw[thin,<->](-0.15,1.5)--++(0.3,0)node[midway,above]{$t$};
    \draw[thin,<->](0.5,1.5)--++(0.2,0)node[midway,above]{20};
    \draw[thin](1.9,1.35)--++(0.3,0);
    \draw[thin](1.9,1.05)--++(0.3,0);
    \draw[thin,<->](2.1,1.05)--++(0,0.3)node[midway,above,sloped]{$t$};
    \end{scope}
  \end{tikzpicture}
\end{document}